LG 42LK450 Service Manual page 19

8. All Source Audio
Check the TV Speaker Menu.
(Menu -> Sound -> TV Speaker)
On
Check AMP IC(IC501) Power
24V, 3.3V.
ok
Check Mstar AUDIO_MASTER_CLK
R148.
ok
Check AMP I2C Line
R140, R141.
ok
Check Mstar I2S Output
IC501 9,10,11 Pin.
ok
Check Output Signal P501
1, 2, 3, 4 pin.
ok
Check Connector & P501.
ok
Check speaker resistance
and connector damage.
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Only for training and service purposes
Off
Toggle the Menu.
No
Replace Amp IC(IC501).
No
Replace Mstar(IC101) o r Main Board.
No
Check signal line. Or replace Mstar(IC101).
No
Check signal line. Or replace Mstar(IC101).
No
Replace Audio AMP IC(IC501).
No
Replace connector.
if found to be damaged.
No
Replace speaker.
- 19 - LGE Internal Use Only